| 摘要 |
A cold work steel has the following chemical composition in weight-%: 1.25 -1.75 % (C+N), however at least 0.5 % C 0.1 - 1.5 % Si 0.1 - 1.5 % Mn 4.0 - 5.5 % Cr 2.5 - 4.5 % (Mo+W/2), however max. 0.5 % W 3.0 - 4.5 % (V+Nb/2), however max. 0.5 % Nb max 0.3 % S balance iron and unavoidable impurities, and a microstructure which in the hardened and tempered condition of the steel contains 6-13 vol-% of vanadium-rich MX-carbides, -nitrides and/or carbonitrides which are evenly distributed in the matrix of the steel, where X is carbon and/or nitrogen, at least 90 vol-% of said carbides, nitrides and/or carbonitrides having an equivalent diameter, Deq, which is smaller than 3.0 ~m; and totally max. 1 vol-% of other, possibly existing carbides, nitrides or carbonitrides.
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